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41.
Clematis sect. Brachiatae is revised in this paper. Twenty-four species and four varieties are recognized. They are keyed, described, and illustrated in most cases, and classified into two series. Brief taxonomic history and geographical distribution of the section are given, and its systematic position and origin are discussed. A western Himalayan species, C. graveolens Lindl., which has long been misplaced in the C. orientalis group (sect. Meclatis), is transferred to sect. Brachiatae on the basis of its floral structure being identical with that of C. brachiata Thunb. and its allies. Two new combinations, sect. Brachiatae Snoeijer ser. Wightianae (W. T. Wang) W. T. Wang and ser. Dissectae (W. T. Wang) W. T. Wang, are made, and two species, C. zaireensis W. T. Wang and C. bowkeri Burtt Davy, are described as new.  相似文献   
42.
Polygonum sect.Tovara includes three controversial species;P. virginianum, P. filiforme, andP. neofiliforme. The flavonoid chemistry of these was examined to provide additional information on their delimitation and levels of differentiation. Eight flavonoid compounds were isolated and identified, all of which were 3-O-glycosides of the flavonols kaempferol, quercetin, and myricetin, and their acylated derivatives. Although they exhibit relatively simple flavonoid profiles, the three taxa are readily distinguished by their flavonoid constituents. In addition, they show fundamental differences in flavonol types and glycosylation patterns. These results, in conjunction with evidence from the morphology, strongly suggest thatP. virginianum, P. filiforme, andP. neofiliforme are closely allied but distinct species.  相似文献   
43.
为选育金花茶优良品种,以7种金花茶组(Camellia sect. Chrysantha)植物成熟叶片为试材,对其总黄酮、茶多酚、总多糖、总皂苷、总氨基酸及维生素E等6种营养物质及K、Ca、Na、Fe、Mn、Zn、Se等7种矿质元素含量进行测定比较,通过聚类分析,考查不同金花茶组植物叶片间存在的药用价值差异。结果表明,7种金花茶组植物叶片的营养成分含量丰富且存在显著差异:凹脉金花茶(Camellia impressinervis)的茶多酚含量最高,达7.13%;东兴金花茶(C. tunghinensis)的总皂苷含量最高,达0.41 g·100 g-1;柠檬金花茶(C. limonia)的总黄酮含量最高,达671.67 mg·100 g-1。矿质元素方面各种类均呈现高钾低钠的特征,凹脉金花茶、柠檬金花茶和小果金花茶(C. nitidissima var. microcarpa)K含量高于Ca,且各品种中均检测出Se元素。综合结果表明,凹脉金花茶叶片中茶多酚、总多糖、总氨基酸等各类营养成分含量相对较高,具有潜在的研究与开发价值。  相似文献   
44.
The stelar structure ofAsplenium obtusifolium and its related species (A. repandulum, A. riparium, A. triquetrum, A. volubile, A. purpurascens, A. ortegae, A. delitescens, A. hoffmannii, andA. laetum) in the New World tropics was observed and compared to that of Asian species ofAsplenium sect.Hymenasplenium. Both of the groups were found to share peculiar stelar structures: steles with two meristeles, a broader ventral and a narrower dorsal, each providing one of the two leaf traces; leaf gaps arranged in two rows between the dorsal and ventral strands, which are connected by thin meristeles, delimiting the leaf gaps. These structures are distinct from the radial symmetrical ones general inAsplenium. Together with cytological evidence, this strongly indicates that the New and Old World groups are closely related. Thus, these Neotropical species should be included in sect.Hymenasplenium.  相似文献   
45.
Pollen of the two distylous species which make upLinum sect.Macrantholinum differs from that of other distylous species in the genus in being multiporate and in having much more modest differences in exine sculpturing between grains from long- and short-styled plants. Pollen morphology does not help in relating the two species to others in the genus but does support their retention in a separate section.  相似文献   
46.
The lectotypes of Achillea chillea santolina L. and A. falcata L. (Achillea sect. Achillea) have been confrmed to be in the Clifford Herbarium. A. santolina L. cannot be retained as the generitype, and the selection of A. millefolium L. instead is confirmed. The species concept of the Linnaean A. santolina did not correspond to the post-Linnaean usage of this name. In most cases, A. santolina L. had been confused with A. wilhelmii C. Koch, but morphological differences separate those two species distinctly. The only extant element of A. falcata L. is found in the Clifford Herbarium, and this specimen corresponds principally to what is considered to be A. falcata today. Deviation in leaf structures is due to this material being of cultivated origin.  相似文献   
47.
Chloroplast DNA restriction site variation was examined amongLepidium taxa usually classified in sects.Lepia, Lepiocardamon andCardamon. By using 15 restriction endonucleases, filter hybridization experiments, and comparative mapping procedures, a total of 119 variable restriction sites was detected. Of these, 56 were phylogenetically informative and were used in a cladistic analysis. The resulting phylogenetic tree agrees with results derived from morphology, isozyme electrophoresis and the analysis of glucosinolates. The data suggest: 1) The recognition of sect.Lepia, and 2) that sect.Lepiocardamon has close relationships to sect.Cardamon and that both should be amalgamated. Low rates of interspecific chloroplast DNA sequence divergence in sect.Lepia correlated well with morphological data and isoelectric focusing analysis of Rubisco, suggesting that taxa of sect.Lepia are closely related and most likely have diversified recently.  相似文献   
48.
王文采 《广西植物》2016,36(Z1):31-57
对毛茛科铁线莲属(Clematis)中单型的翅果铁线莲组(sect. Pterocarpa)进行了分类学修订,写出了此组及其惟一种,翅果铁线莲(C. brachyura)的分类学简史和形态描述,给出此种的插图。根据其体态及花构造近似亚洲东部的辣蓼铁线莲(C. mandshurica Rupr.)和圆锥铁线莲(C. terniflora DC.)[二种均为威灵仙组(sect. Clematis)的成员],推测翅果铁线莲可能源自威灵仙组。  相似文献   
49.
Four distinct species ofCortinarius referable to subg.Dermocybe are described from the Cooloola Sand-Mass, Queensland; two are formally recognized asC. alkalivirens, spec. nova andC. chromobasis, spec. nova, whilst notes are provided for the other two. Chemical methods and cladistic studies are applied and indicate a new section of the subgenus is required.Australodermocybe sect. nova is proposed.  相似文献   
50.
小偃麦原生质体培养及植株再生   总被引:3,自引:0,他引:3  
硬粒小麦(Triticum durum Desf.AABB)和中间偃麦革[Elytrigia intermedium(Host)Nevski BBEEFF]的杂种 F_1——小偃麦的幼穗诱导的胚性愈伤组织继代培养近两年后,转入修改的 MS 液体培养基建成胚性细胞悬浮系。从此悬浮系分离的原生质体在修改的 KM_(8p)培养基中培养48小时后出现第一次分裂。15天后,在液体浅层培养条件下的细胞分裂频率为2%;而用1.2%琼脂糖固化进行固体平板培养时,细胞的分裂频率则为12.14%。20—30天后,添加渗透压降低的原生质体培养液。当从原生质体再生的愈伤组织长至2—4mm 大小时,逐步转至生长及分化培养基上再生出完整植株。  相似文献   
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